84 crossfire cuts out when warm

[showtime76]

Hi there I'm looking for help with a 84 crossfire. Misses when it warm on take off. Major hesitation only when warm like a vacume leak but not finding any with carb cleaner. When I smoke tested both IAC valves leaked out smoke this was when the car was off. Should they be closed at this point?

 

[Hot Rod Roy]

I'd suspect a vacuum leak, too. Are the many bolts around the top of your throttle body mounting plate tight? This is a common area for leaks. Since the IAC valves are stepper motors, I really doubt they close when you shut down the engine. They want to be at about the right spot when you re-start the engine.

 

[xfirez51]

IACs will be positioned for startup, so yeah they'll be open. Check TBIs and the manifold top plate
gaskets may need replacing depending on age and DON'T USE silicone sealer for gaskets.

 

[showtime76]

Got the vette running better. It was the computer. That and replaced the spark plug wires and some old vacume lines. Only thing now is my damn smog pump locked up yesterday so now I need a new one. Its like one thing after another with this car. Still fun to drive. Just wish I could find parts a little easier.

 

[xfirez51]

Got the vette running better. It was the computer. That and replaced the spark plug wires and some old vacume lines. Only thing now is my damn smog pump locked up yesterday so now I need a new one. Its like one thing after another with this car. Still fun to drive. Just wish I could find parts a little easier.

Pull the the guts out of the smog pump and just run it as an idler.